Stable (METH)acrylic composition, method for producing said composition and uses thereof

Abstract

The present invention relates to a (meth)acrylic composition, a process for preparing the (meth)acrylic composition and uses of such a (meth)acrylic composition. In particular the present invention relates to a (meth)acrylic composition with increased pot-life, a process for preparing the (meth)acrylic composition and uses of such a (meth)acrylic composition. The invention also relates also to a (meth)acrylic polymeric composite material, comprising or made of a (meth)acrylic composition with increased pot-life, a method for preparing such (meth)acrylic composite material comprising or made of a (meth)acrylic composition with increased pot-life and an object comprising such (meth)acrylic polymeric composite material comprising or made of a (meth)acrylic composition with increased pot-life.

Description

STABLE (METH) CRYLIC COMPOSITION , METHOD FOR PRODUCING SAID COMPOSITION AND USES THEREOF[Field of the invention]

[0001] The present invention relates to a (meth) acrylic composition, a process for preparing the (meth) acrylic composition and uses of such a (meth) acrylic composition .

[0002] In particular the present invention relates to a (meth ) acrylic composition with increased pot-life , a process for preparing the (meth ) acrylic composition and uses of such a (meth ) acrylic composition .

[0003] The invention also relates also to a (meth ) acrylic polymeric composite material , comprising or made of a (meth ) acrylic composition with increased pot-life , a method for preparing such (meth ) acrylic composite material comprising or made of a (meth ) acrylic composition with increased pot-life and an obj ect comprising such (meth) acrylic polymeric composite material comprising or made of a (meth) acrylic composition with increased pot-life .[Technical problem]

[0004] Many materials used today are not pure materials based on one compound but are a blend of several components or are a composite materials .

[0005] A composite material is a macroscopic combination of two or more non-miscible materials . The composite material constitutes at least of a matrix material , for example a polymeric material , that forms a continuous phase for the cohesion of the structure and a reinforcing material with various architectures for the mechanical properties .

[0006] The aim in using composite materials is to achieve a performance from the composite material that is not available from its separate constituents if used alone . Consequently, composite materials are widely used in several industrial sectors as for example building, automotive , nautical or marine , aerospace ,transport , leisure , electronics , and sport notably due to their better mechanical performance ( higher tensile strength, higher tensile modulus , and higher fracture toughness ) in comparison with homogenous materials and their low density .

[0007] The most important class in view of volume in commercial industrial scale , are composites with organic matrices , where the matrix material is generally a polymer . The principal matrix or continuous phase of a polymeric composite material is either a thermoplastic polymer or a thermosetting polymer .

[0008] One way for preparing a polymeric composite material based on thermoplastic polymers is by using a liquid polymer composition comprising a monomer and other components required, commonly known as a "syrup" . Such a syrup is used for blending with a mineral filler or for impregnating the reinforcing material , for example a fibrous substrate ; followed by polymerization . However , the other components required for the composition can influence the stability of the monomer . This can already start partly polymerization so that the liquid polymer composition is gelling and not usable anymore . In a worst case such a liquid polymer composition cannot even be stocked for one day even at 25 ° c .

[0009] Before using such a liquid polymer composition, it might have to be stocked and transported after preparation to the place where the polymerization takes place . So , a certain shelf-life is required . Even if the composition of prepared at the place where the polymerization takes place , a certain pot-life is required .

[0010] At the end of the use of obj ect or article comprising the composite material , said obj ect or article should be easily recyclable .[Oil ] There is a need for (meth) acrylic compositions that have a medium to long pot life .

[0012] There is also a need to propose a process for making (meth ) acrylic compositions that have a medium to long pot life .

[0013] By long pot life is meant at least one day at 25 ° C , preferably several days at 25 ° C , or even up to at least one week at 25 ° C , or up to at least one months at 25 ° C and more preferably up to at least1 month at 40°C without significant polymerization, meaning no significant increase of viscosity.[BACKGROUND OF THE INVENTION] Prior art

[0014] The document WO2013 / 056845 discloses a composite material via in-situ polymerization of thermoplastic (meth) acrylic resins. The polymeric composite material obtained by in-situ polymerization of a thermoplastic (meth) acrylic resin and a fibrous material containing long fibers and its use, a process for making such a composite material and manufactured mechanical or structured part or article comprising this polymeric composite material. The document does not disclose anything about its pot-life.

[0015] The document W02014 / 013028 an impregnation process for a fibrous substrate, a liquid (meth) acrylic syrup for the impregnation process, its method of polymerization and structured article obtained thereof. The liquid (meth) acrylic syrup comprises a (meth) acrylic polymer, a (meth) acrylic monomer and at least one initiator or initiating system for starting the polymerization of the (meth) acrylic monomer. The document does not disclose anything about its pot-life.

[0016] The document WO2014 / 174098 discloses a liquid (meth) acrylic syrup its method of polymerization. The initiating system of said syrup comprises at least one accelerator, at least one organic aldehyde and a peroxy compound and organic peracid.

[0017] The document W003 / 008463 discloses method for polymerising vinyl monomers and / or oligomers comprising at least a vinyl radical. Additionally the composition comprises compound giving a dioxygen as a peroxide, an aldehyde and an accelerator.

[0018] The document WO2020 / 247549 discloses a thermoplastic gel coat. The gel coat is based on liquid thermoplastic (meth) acrylic resin comprising a blend of (meth) acrylic polymer(s) , (meth) acrylic monomer (s) , and initiator. The liquid thermoplastic (meth) acrylic resin can optionally comprise other additives .

[0019] The compositions comprise usually an (meth) acrylic monomer, which is stabilized itself, but once the other components for composition to be polymerized have been added, except for the polymerization initiator, the pot life decreases.

[0020] None of the cited prior art discloses a liquid (meth) acrylic syrup having a sufficient pot-life.[Brief description of the invention]

[0021] Surprisingly it has been found that a (meth) acrylic composition (MCI) comprising:(a) 100 parts by weight of a liquid (meth) acrylic syrup (LSM1) comprising :(ai) from 1% by weight to 50% by weight of one or more(meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more(meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer,(b) an inhibitor(c) at least one organic aldehyde(d) a transition metal(c) optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator, allows to provide a composition that possesses a sufficient potlife .

[0022] Surprisingly it has also been found that a (meth) acrylic composition (MCI) comprising:(a) 100 parts by weight of a liquid (meth) acrylic syrup (LSM1) comprising :(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer,(b) between 0.005 part and 1 part by weight of an inhibitor(c) between 0.5 part and 10 parts by weight of one organic aldehyde(d) between 0.01 part and 4 parts by weight a transition metal(c) optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator, allows to provide a composition that possesses a sufficient potlife .

[0023] Surprisingly it has been found that a process for preparing a (meth) acrylic composition (MCI) , said process is comprising the following steps :(i) providing 100 parts by weight of (a) a liquid (meth) acrylic syrup (LSM1) comprising:(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(ii) providing (b) an inhibitor, (c) at least one organic aldehyde and (d) a reducing agent(iii) optionally providing from 0.01 part by weight to 10 parts by weight of a polymerization initiator(iv) mixing the components allows to prepare a composition that possesses a sufficient potlife .[Detailed description of the invention]

[0024] According to a first aspect, the present invention relates to a (meth) acrylic composition (MCI) , said composition is comprising:(a) 100 parts by weight of a liquid (meth) acrylic syrup having a recycled content of at least lwt% comprising:(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers Pl, and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers Ml, each monomer Ml comprising only one (meth) acrylic function per monomer,(b) an inhibitor(c) at least one organic aldehyde(d) a reducing agent(c) optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator.

[0025] According to a second aspect, the present invention relates to a (meth) acrylic composition (MCI) , said composition is comprising:(a) 100 parts by weight of a liquid (meth) acrylic syrup (LSM1) comprising :(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers Pl, and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers Ml, each monomer Ml comprising only one (meth) acrylic function per monomer,(b) an inhibitor(c) at least one organic aldehyde(d) a reducing agent(c) optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator.

[0026] According to a third aspect, the present invention relates to a process for preparing a (meth) acrylic composition (MCI) comprising following steps :(i) providing 100 parts by weight of (a) a liquid (meth) acrylic syrup (LSM1) comprising:(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more(meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(ii) providing (b) an inhibitor, (c) at least one organic aldehyde and (d) a reducing agent(iii) optionally providing from 0.01 part by weight to 10 parts by weight of a polymerization initiator(iv) mixing the components.

[0027] According to a fourth aspect, the present invention relates to a process for preparing a (meth) acrylic composition (MCI) , said process is comprising following steps :(i) providing 100 parts by weight of (a) a liquid (meth) acrylic syrup (LSM1) comprising:(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(32) from 50% by weight to 99% by weight of one or more(meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer,(ii) providing (b) between 0.005 part and 1 part by weight of an inhibitor, (c) between 0.5 part and 10 parts by weight of one organic aldehyde and (d) between 0.01 part and 4 parts by weight a transition metal ,(iii) providing optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator(iv) mixing the components.

[0028] According to a fifth aspect the present invention relates to the use of a (meth) acrylic composition (MCI) according to the first aspect or the second aspect to prepare a (meth) acrylic polymeric material (MPC1) or (meth) acrylic polymeric composite material (MPCM1) .

[0029] According to a sixth aspect the present invention relates to a (meth) acrylic polymeric material (MPC1) or (meth) acrylic polymeric composite material (MPCM1) prepared by polymerization of the (meth) acrylic composition (MCI) according to the first aspect or the second aspect.

[0030] According to a seventh aspect the present invention relates to a process for preparing a (meth) acrylic polymeric material (MPC1) , said process comprises the following steps:(i) providing a (meth) acrylic composition (MCI) according to first or second aspect,(ii) polymerizing the (meth) acrylic composition (MCI) .

[0031] According to an eight aspect the present invention relates to a process for preparing a (meth) acrylic polymeric composite material (MPCM1) , said process comprises the following steps:(i) providing a (meth) acrylic composition (MCI) according to first or second aspect,(ii) bringing the (meth) acrylic composition (MCI) in contact with a reinforcing material,( iii ) polymerizing the (meth ) acrylic composition (MCI ) .

[0032] The term " (meth) acrylic monomer" covers both an acrylic monomer and a methacrylic monomer . Similarly, the term " (meth) acrylic polymer" covers not only an acrylic homopolymer but also a methacrylic homopolymer , an acrylic copolymer and a methacrylic copolymer .

[0033] By the term "PMMA" as used are denoted homo- and copolymers of methylmethacrylate (MMA) , for the copolymer of MMA the weight ratio of MMA inside the PMMA is at least 50 wt% .

[0034] By the term "initiator" as used is denoted a chemical species that forms compound or an intermediate compound that starts the polymerization of a monomer , that to capable of linking successively with a large number of other monomers into a polymeric compound .

[0035] By the term "polymer composite" as used is denoted a multicomponent material comprising multiple different phase domains in which at least one type of phase domain is a continuous phase and in which at least one component is a polymer .

[0036] By the term "thermoplastic" as used is denoted a polymer that turns to a liquid or becomes more liquid or less viscous when heated and that can take on new shapes by the application of heat and optionally pressure . This applies also for slightly crosslinked thermoplastic polymers that can be thermoformed when heated above the softening temperature.

[0037] By saying that a range from x to y in the present invention, it is meant that the upper and lower limit of this range are included, equivalent to at least x and up to y .

[0038] By saying that a range is between x and y in the present invention, it is meant that the upper and lower limit of this range are excluded, equivalent to more than x and less than y .

[0039] The liquid (meth ) acrylic syrup ( LSM1 ) of the composition according to the invention comprises ( ai ) a (meth ) acrylic polymer ( Pl ) and ( a2 ) a (meth ) acrylic monomer (Ml ) .

[0040] The liquid (meth ) acrylic syrup (LSM1 ) according to the (meth ) acrylic composition (MCI ) of invention comprises between lwt%and 50wt% of at least a (meth) acrylic polymer (Pl) and between 50wt% and 99wt% of at least a (meth) acrylic monomer (Ml) .

[0041] Preferably the liquid (meth) acrylic syrup (LSM1) comprises between 2wt% and 50wt% of a (meth) acrylic polymer (Pl) and between 50wt% and 98wt% of a (meth) acrylic monomer (Ml) , more preferably between 2wt% and 40wt% of a (meth) acrylic polymer (Pl) and between 60wt% and 98wt% of a (meth) acrylic monomer (Ml) , still more preferably between 3wt% and 40wt% of a (meth) acrylic polymer (Pl) and between 60wt% and 97wt% of a (meth) acrylic monomer (Ml) , advantageously between 3wt% and 35wt% of a (meth) acrylic polymer (Pl) and between 65wt% and 97wt% of a (meth) acrylic monomer (Ml) and more advantageously between 3wt% and 30wt% of a (meth) acrylic polymer (Pl) and between 70wt% and 97wt% of a (meth) acrylic monomer (Ml) .

[0042] The dynamic viscosity of the liquid (meth) acrylic syrup (LMS1) is in a range from 10 mPa*s to 10000 mPa*s, preferably from 20 mPa*s to 7000 mPa*s and advantageously from 20 mPa*s to 5000 mPa*s and more advantageously from 20 mPa*s to 2000 mPa*s and even more advantageously between 20mPa*s and 1000 mPa*s. The viscosity of the syrup can be easily measured with a Rheometer or viscosimeter. The dynamic viscosity is measured at 23°C. If the liquid (meth) acrylic syrup has a Newtonian behaviour, meaning no shear thinning, the dynamic viscosity is independent of the shearing in a rheometer or the speed of the mobile in a viscometer. If the liquid composition has a non-Newtonian behaviour, meaning shear thinning, the dynamic viscosity is measured at a shear rate of Is-1at 23°C.

[0043] As regards the liquid (meth) acrylic syrup (LSM1) , it comprises (32) the (meth) acrylic monomer (Ml) and (ai) the (meth) acrylic polymer (Pl) . Once the (meth) acrylic composition (MCI) has been polymerized, the (meth) acrylic monomer (Ml) polymerizes eventually with other (meth) acrylic monomers and is transformed to a (meth) acrylic polymer (P2) comprising the monomeric units of (meth) acrylic monomer (Ml) and other possible comonomers.

[0044] The liquid (meth) acrylic syrup (LSM1) of the (meth) acrylic composition (MCI) according to the invention may comprise only one (meth) acrylic polymer (Pl) , but may equally comprise a mixture of two, three or even more (meth) acrylic polymers (Pl) . If there is amixture of different (meth) acrylic polymer (Pl) , the difference is the composition of the respective (meth) acrylic polymer (Pl) or the molecular weight of the respective (meth) acrylic polymer (Pl) or both .

[0045] The or each (meth) acrylic polymer (Pl) included in the liquid (meth) acrylic syrup may in particular be chosen from:. polyalkyl acrylates which comprise alkyl acrylate homopolymers and alkyl acrylate copolymers, and. polyalkyl methacrylates which comprise alkyl methacrylate homopolymers and alkyl methacrylate copolymers.

[0046] According to a preferred embodiment, the or each (meth) acrylic polymer (Pl) is a polymethyl methacrylate (PMMA) , it being understood that, as indicated above, the polymethyl methacrylate (PMMA) may denote a methyl methacrylate (MMA) homopolymer or an MMA copolymer .

[0047] In particular, in the case where the liquid (meth) acrylic syrup (LMS1) comprises a mixture of two or more polymethyl (meth) acrylates (Pl) , this mixture may be formed by mixing at least two MMA homopolymers having a different molecular weight, by mixing at least two MMA copolymers having an identical monomer composition and a different molecular weight, by mixing at least two MMA copolymers having a different monomer composition or by mixing at least one MMA homopolymer and at least one MMA copolymer.

[0048] According to a first preferred embodiment the (meth) acrylic polymer (Pl) is chosen from a methyl methacrylate homopolymer or a methyl methacrylate copolymer or a mixture thereof, methyl methacrylate advantageously representing at least 50% by weight of the or of each (meth) acrylic polymer (Pl) .

[0049] According to one embodiment of the invention, methyl methacrylate represents at least 55% by weight of the or each (meth) acrylic polymer (Pl) .

[0050] According to another particular embodiment, the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) comprises at least 70%, advantageously at least 80%, preferentially at least 90% and more preferentially at least 95% by weight of methyl methacrylate.

[0051] When the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is a methyl methacrylate (MMA) copolymer, it maycomprise at least one comonomer containing at least one ethylenic unsaturation and which is capable of copolymerizing with methyl methacrylate. Among these comonomers, mention may notably be made of acrylic and methacrylic acids and alkyl (meth) acrylates in which the alkyl group contains from 1 to 12 carbon atoms. Alkyl (meth) acrylates means an alkyl ester of acrylic acid or methacrylic acid. As examples of comonomers, mention may be made of methyl acrylate and ethyl, butyl or 2-ethylhexyl (meth) acrylate .

[0052] Advantageously, the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate and of an alkyl acrylate or an alkyl methacrylate in which the alkyl group contains from 1 to 12 carbon atoms, advantageously from 1 to 6 carbon atoms and preferentially from 1 to 4 carbon atoms .

[0053] According to a first preferred embodiment, when the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is a methyl methacrylate (MMA) copolymer, this methyl methacrylate (MMA) copolymer comprises from 70% to 99.9%, advantageously from 80% to 99.9%, preferentially from 90% to 99.9% and more preferentially from 95% to 99.9% by weight of methyl methacrylate and from 0.1% to 30%, advantageously from 0.1% to 20%, preferentially from 0.1% to 10% and more preferentially from 0.1% to 5% by weight of at least one comonomer containing at least one ethylenic unsaturation that can copolymerize with methyl methacrylate. Preferably, the comonomer or each comonomer is chosen from methyl acrylate and ethyl acrylate.

[0054] In an advantageous variant of the first preferred embodiment, when the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is a methyl methacrylate (MMA) copolymer, the (meth) acrylic polymer (Pl) is a copolymer of methyl methacrylate and of alkyl acrylate .

[0055] In a preferred variant of the first preferred embodiment, when the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is a methyl methacrylate (MMA) copolymer, the (meth) acrylic polymer (Pl) is a copolymer of methyl methacrylate and of methyl acrylate or ethylacrylate.

[0056] According to a second preferred embodiment, when the or each (meth) acrylic polymer (Pl) is a methyl methacrylate (MMA) copolymer,this methyl methacrylate (MMA) copolymer comprises from 50% to 99.9%, advantageously from 52% to 99.9%, preferentially from 53% to 99.9% and more preferentially from 55% to 99.9% by weight of methyl methacrylate and from 0.1% to 50%, advantageously from 0.1% to 48%, preferentially from 0.1% to 47% and more preferentially from 0.1% to 45% by weight of at least one comonomer containing at least one ethylenic unsaturation that can copolymerize with methyl methacrylate. Preferably, the or each comonomer is chosen from methyl acrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate or butyl methacrylate.

[0057] The weight-average molecular weight, noted as Mw, of the or each (meth) acrylic polymer Pl is generally high and may consequently be greater than 40 000 g / mol, advantageously greater than 45 000 g / mol and preferentially greater than 50 000 g / mol. The weightaverage molecular weight may be measured by size exclusion chromatography (SEC) .

[0058] The (meth) acrylic polymer (Pl) , if not crosslinked, usually has a melt mass-flow rate (MFR) ISO 1133-2:2011 (230°C / 3.8 kg) of between 0.1 g / 10 min and 20 g / 10 min or the melt mass-flow rate is between 0.2 g / 10 min and 18 g / 10 min, or between 0.3 g / 10 min and 16 g / 10 min or between 0.4 g / 10 min and 13 g / 10 min.

[0059] The liquid (meth) acrylic syrup (LSM1) of the (meth) acrylic composition (MCI) according to the invention may comprise only one (meth) acrylic monomer (Ml) , but may equally comprise a mixture of two, three or even more (meth) acrylic monomers (Ml) . This would be (meth) acrylic monomer (Mia) , (meth) acrylic monomer (Mlb) , (meth) acrylic monomers (Mlc) and so on.

[0060] Whether the liquid (meth) acrylic syrup comprises one or more (meth) acrylic monomers (Ml) , the (meth) acrylic monomer (Ml) or each (meth) acrylic monomer (Ml) comprises only one (meth) acrylic function per monomer .

[0061] As regards the (meth) acrylic monomer (Ml) , the monomer is chosen from alkyl acrylic monomers, alkyl methacrylic monomers, hydroxyalkyl acrylic monomers and hydroxyalkyl methacrylic monomers, and mixtures thereof. Alkyl acrylic monomer or alkylmethacrylic monomer means an alkyl ester of acrylic acid or methacrylic acid.

[0062] Preferably, the (meth) acrylic monomer (Ml) is chosen from hydroxyalkyl acrylic monomers, hydroxyalkyl methacrylic monomers, alkyl acrylic monomers, alkyl methacrylic monomers and mixtures thereof, the alkyl group containing from 1 to 22 linear, branched or cyclic carbons; the alkyl group preferably containing from 1 to 12 linear, branched or cyclic carbons.

[0063] Advantageously, the (meth) acrylic monomer (Ml) is chosen from methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, n-butyl methacrylate, isobutyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, isobornyl acrylate, isobornyl methacrylate, hydroxyethyl acrylate and hydroxyethyl methacrylate, and mixtures thereof.

[0064] According to a preferred embodiment, at least 50% by weight and preferably at least 60% by weight of the (meth) acrylic monomer (Ml) is methyl methacrylate.

[0065] According to a first more preferred embodiment, at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, advantageously at least 80% by weight and even more advantageously 90% by weight of the monomer (Ml) is methyl methacrylate or a mixture of methyl methacrylate with optionally at least one other monomer.

[0066] According to a second more preferred embodiment the monomer (Ml) is methyl methacrylate.

[0067] In a first variant of the invention, the liquid (meth) acrylic syrup (LSM1) comprises:(ai) from 3% by weight to 45% by weight and preferentially from 3% by weight to 40% by weight of the (meth) acrylic polymer (s) ( Pl ) , and(a2) from 55% by weight to 97% by weight and preferentially from 60% by weight to 97% by weight of the (meth) acrylic monomer (s) (Ml) .

[0068] In a second variant of the invention, the liquid (meth) acrylic syrup (LSM1) comprises:(ai) from 10% by weight to 35% by weight and preferentially from 12% by weight to 35% by weight and more preferentially from 12% by weight to 30% by weight and still more preferentially from 15% by weight to 30% by weight and even more preferentially from 17% by weight to 30% by weight of the (meth) acrylic polymer (s) (Pl) , and(a2) from 65% by weight to 90% by weight and preferentially from 65% by weight to 88% by weight and more preferentially from 70% by weight to 88% by weight and still more preferentially from 70% by weight to 85% by weight and even more preferentially from 70% by weight to 83% by weight of the (meth) acrylic monomer(s) (Ml) .

[0069] In an advantageous variant, the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) and the (meth) acrylic monomer (Ml) or each (meth) acrylic monomer (Ml) of the liquid (meth) acrylic syrup comprise at least one same (meth) acrylic unit, such a variant making it possible to optimize the solubility of the (meth) acrylic polymer(s) (Pl) in the (meth) acrylic monomer(s) (Ml) .

[0070] Preferentially, the (meth) acrylic polymer (Pl) or each (meth) acrylic polymer (Pl) is chosen from a homopolymer of methyl methacrylate or copolymer of methyl methacrylate and of methyl acrylate and a copolymer of methyl methacrylate and of ethyl acrylate or a copolymer of methyl methacrylate and of butyl acrylate or a copolymer of methyl methacrylate and of butyl methacrylate, the respective comonomer being present at most at 45wt% in the copolymer.

[0071] In a first advantageous variant, the liquid (meth) acrylic syrup comprises a (meth) acrylic polymer (Pl) , rather than a mixture of (meth) acrylic polymers (Pl) .

[0072] In a second advantageous variant, the liquid (meth) acrylic syrup comprises a mixture of two (meth) acrylic polymers (Pl) .

[0073] Stabilizers are also present in the liquid (meth) acrylic syrup (LSM1) to prevent spontaneous polymerization of the (meth) acrylic monomer(s) (Ml) . Usually the (meth) acrylic monomer (Ml) comprises a stabilizer .

[0074] These stabilizers may notably be chosen from hydroquinone (HQ) , hydroquinone monomethyl ether (HQME) , 2 , 6-di-tert-butyl-4-methylphenol (BHT) , 2 , 6-di-tert-butyl-4-methoxyphenol (Topanol O) and 2 , 4-dimethyl-6-tert-butylphenol (Topanol A) .

[0075] These stabilizers may be present, in the liquid (meth) acrylic syrup, in a proportion of not more than 5 parts by weight, advantageously not more than 4 parts by weight and preferentially in a proportion of between 0.3 and 3 parts by weight, per 100 parts by weight of the sum of the (meth) acrylic polymer (s) (Pl) and of the (meth) acrylic monomer(s) (Ml) .

[0076] The component (b) an inhibitor is also part of the (meth) acrylic composition (MCI) .

[0077] The inhibitor is preferably chosen from 4-hydroxy-2 , 2 , 6, 6- tetramethylpiperidin-l-oxyl ( 4-Hydroxy-TEMPO or TEMPOL) or (2, 2, 6, 6-Tetramethylpiperidin-l-yl) oxyl (TEMPO) .

[0078] The component (b) the inhibitor of the (meth) acrylic composition (MCI) , presents between 0.005 part and 1 parts by weight for 100 parts by weight of a liquid (meth) acrylic syrup (LMS1) , preferably between 0.01 and 0.5 parts.

[0079] The component (c) the at least one organic aldehyde of the (meth) acrylic composition (MCI) can be aliphatic or aromatic.

[0080] The aliphatic part organic aldehyde can be linear, cyclic or branched, but also be saturated or unsaturated.

[0081] The organic aldehyde comprises between 3 and 30 carbon atoms. It has a general formula R-CH=O, in which R represents a cyclic hydrocarbon-based chain or a linear or branched hydrocarbon-based chain, R comprising from 2 to 29 carbon atoms, preferably from 3 to 15, optionally comprising one or more unsaturation ( s ) in the form of double bonds and being optionally substituted with one or more hydroxyl groups .

[0082] Mention may be made of propionaldehyde, butyraldehyde, valeraldehyde, capraldehyde , benzaldehyde, geranial, neral, citronellal and in general, aldehydes containing hydrocarbon-based groups comprising one or more unsaturations of olefinic type and also mixtures of two or more thereof in all proportions .

[0083] In one embodiment the organic aldehyde is chosen from propionaldehyde, butyraldehyde, valeraldehyde, capraldehyde,benzaldehyde, geranial, neral, citronellal and also mixtures of two or more thereof in all proportions.

[0084] In one embodiment the organic aldehyde chosen from 3,7- demethylocta-2 , 6-dienal .

[0085] The component (c) the at least one organic aldehyde of the (meth) acrylic composition (MCI) is present between 0.5 part and 10 parts by weight for 100 parts by weight of a liquid (meth) acrylic syrup (LMS1) , preferably between 0.5 part and 8 parts by weight, more preferably between 0.5 part and 6 parts by weight.

[0086] The component (d) the transition metal of the (meth) acrylic composition (MCI) it can be chosen from the 4thperiod of the periodic system of elements.

[0087] Advantageously the transition metal is chosen from Manganese, Cobalt, Iron or Copper and more advantageously Manganese, Iron, Copper or mixtures thereof.

[0088] The transition metal can be in form a metal salt or a mixture of metal salts or an organic complex comprising the transition metal.

[0089] The component (d) the transition metal of the (meth) acrylic composition (MCI) is present between 0.01 part and 4 parts by weight for 100 parts by weight of the liquid (meth) acrylic syrup (LMS1) , preferably between 0.02 part and 4 parts and more preferably between 0.05 part and 3 parts. The quantity of the component (d) the transition metal is calculated on the transition metal part only.

[0090] The (meth) acrylic composition (MCI) can also comprise an antioxidant (f) .

[0091] Preferably the antioxidant (f) is chosen from a phosphite or a thioether or a mixture of phosphite and thioether.

[0092] The phosphite is organic. It can be for example tris (2,4-di- tert-butylphenyl ) phosphite, tris (nonylphenyl ) phosphite or tris ( 2 , 6-dimethylphenyl ) phosphite .

[0093] The thioether can be for example didodecyl-3 , 3 ' - thiodipropionate .

[0094] The component (f) the the antioxidant of the (meth) acrylic composition (MCI) if present, is between 0.001 part and 4 parts by weight for 100 parts by weight of the liquid (meth) acrylic syrup(LMS1) , preferably between 0.01 parts and 4 parts and more preferably 0.1 and 3 parts .

[0095] The (meth) acrylic composition (MCI) according to one aspect of the invention also comprises a polymerization initiator, the function of which is to ensure the start of polymerization of the (meth) acrylic monomer (Ml) .

[0096] The polymerization initiator may be chosen from organic peroxides, peroxy esters, peroxy acetals and azo compounds.

[0097] The polymerization initiator may in particular be chosen from diacyl peroxides, peroxy esters, peroxydicarbonates, dialkyl peroxides, peroxyacetals, hydroperoxide or peroxyketale .

[0098] The (meth) acrylic composition (MCI) according to the invention may comprise from 0.01 part by weight to 10 parts by weight of polymerization initiator or from 0.01 part by weight to 5 parts.

[0099] According to a particular embodiment, the (meth) acrylic composition MCI according to the invention comprises from 0.02 part by weight to 4 parts by weight and advantageously 0.03 part by weight to 3 parts by weight of polymerization initiator per 100 parts by weight of the liquid (meth) acrylic syrup.

[0100] The (meth) acrylic composition MCI according to the invention may also effectively further according to certain aspects comprise a polymerization activator or accelerator.

[0101] According to a particular embodiment, the (meth) acrylic composition according to the invention comprises between lOOppm and 10 OOOppm, advantageously between lOOppm and 7 OOOpmm and preferably between 200ppm and 5 OOOppm of polymerization activator or accelerator per 100 parts by weight of the (meth) acrylic syrup.

[0102] The present invention relates also to a process for preparing a (meth) acrylic composition (MCI) .

[0103] According to the invention, this process comprises the steps: providing the respective components and iv) mixing the components .

[0104] Step iv) of the preparing process according to the invention is performed by mixing all of the components included in the (meth) acrylic composition (MCI) . In one embodiment care is beingtaken to prepare, firstly, the liquid (meth) acrylic syrup (LMS1) and then to introduce, into this (meth) acrylic syrup (LSM1) the odour masking agent and where appropriate, the polymerization activator or accelerator, the polymerization initiator being introduced last.

[0105] This mixing may be manual or may be performed using a mixing means .

[0106] Optionally, the mixing is performed by stirring, and for a time of between 1 minutes and 36 hours, advantageously between 2 minutes and 24 hours, more advantageously between 3 minutes and 24 hours and preferentially between 4 minutes and 24 hours.

[0107] The (meth) acrylic composition (MCI) comprising all the components or the optionally other added components has a viscosity between 10mPa*s and 10 000 mPa*s at 23°C.

[0108] Preferably the viscosity of (meth) acrylic composition (MCI) comprising the components at 23°C is in a range from 50 mPa*s to 10 000 mPa*s, more preferably from 50 mPa*s to 9 000 mPa*s, still more preferably from 50 mPa*s to 8 000 mPa*s, even still more preferably from 50 mPa*s to 7 500 Pa*s, even still more preferably between 50mPa*s and 7 000 mPa*s, advantageously between 50mPa*s and 6 000mPa*s and more advantageously between 50mPa*s and 5 000mPa*s.

[0109] The (meth) acrylic composition (MCI) according to the first aspect or the second aspect is used to prepare a (meth) acrylic polymeric material (MPC1) or (meth) acrylic polymeric composite material (MPCM1) .

[0110] The (meth) acrylic polymeric material (MPC1) or the (meth) acrylic polymeric composite material (MPCM1) is prepared by polymerization of the (meth) acrylic composition (MCI) according to the first aspect or the second aspect.

[0111] The invention relates to a process for preparing a (meth) acrylic polymeric material (MPC1) , said process comprises the following steps :(i) providing a (meth) acrylic composition (MCI) according to first or second aspect,(ii) polymerizing the (meth) acrylic composition (MCI) .

[0112] The invention relates to a process for preparing a (meth) acrylic polymeric composite material (MPCM1) , said process comprises the following steps :(i)providing a (meth) acrylic composition (MCI) according to first or second aspect,(ii) bringing the (meth) acrylic composition (MCI) in contact with a reinforcing material,(iii) polymerizing the (meth) acrylic composition (MCI) .

[0113] In one embodiment, the reinforcing material is a fibrous substrate. The fibers of the fibrous substrate in the present invention are long fibers or continuous fibers. The fibrous substrate comprises preferably fibers having an aspect ratio of at least 1000, preferably at least 2000, more preferably at least 4000, advantageously at least 7000 and most advantageously at least 10 000 or continuous fibers. A fiber is defined by its aspect ratio, which is the ratio between the length and diameter of the fiber.

[0114] The fibrous substrate of the present invention is chosen from plant fibers, wood fibers, animal fibers, mineral fibers, synthetic polymeric fibers, glass fibers and carbon fibers, and mixtures thereof .

[0115] The fibers of the fibrous material have a diameter between 0.005 pm and 100 pm, preferably between 1 pm and 50 pm, more preferably between 5 pm and 30 pm and advantageously between 10 pm and 25 pm.

[0116] In another embodiment, the reinforcing material is a mineral filler. The mineral filler C may notably comprise a filler Cl chosen from quartz, granite, marble, feldspar, clay, glass, ceramics, mica, graphite, silicates, carbonates, carbides, sulfates, silicates, hydroxides, metal oxides, metals and mixtures thereof.

[0117] The step of bringing the (meth) acrylic composition (MCI) in contact with a reinforcing material

[0118] With regard to the process for preparing a (meth) acrylic polymeric composite material (MPCM1) several methods could be used, notably including the step bringing the (meth) acrylic composition (MCI) in contact with a reinforcing material for a fibrous substrate. One can mention infusion, vacuum bag moulding, pressure bag molding, autoclave molding, resin transfer moulding (RTM) , reaction injectionmolding (RIM) reinforced reaction injection molding (R-RIM) and variants thereof, press molding or compression molding, pultrusion and filament winding.

[0119] With regard to the applications of (meth) acrylic polymeric composite material (MPCM1) , one can mention automotive and motorsports applications as for example pressure vessel, ballistic & defense applications, marine applications, railroad and transport applications, sport, leisure and recreational applications, arts and entertainments applications, aeronautic and aerospace applications, construction and civil engineering applications, oil & gas applications, renewable applications such as photovoltaic applications and wind energy applications .

[0120] As regards the use of mechanical parts made of (meth) acrylic polymeric composite material (MPCM1) thus manufactured, mention may be made of automotive applications, transport applications such as buses or lorries, marine applications, railroad applications, sport, aeronautic and aerospace applications, photovoltaic applications, computer-related applications, construction and building applications, telecommunication applications and wind energy applications .

[0121] The mechanical part made of (meth) acrylic polymeric composite material (MPCM1) is especially a motor vehicle part, boat part, bus part, train part, sport article, plane or helicopter part, space ship or rocket part, photovoltaic module part, a pressure vessel, a material for construction or building, wind turbine part for example spar cap of girder of wind turbine blade, furniture part, construction or building part.[Methods ]

[0122] The weight-average molecular weight may be measured by size exclusion chromatography (SEC) . The chromatography column is calibrated with PMMA standards having a molecular weight between 402g / mol and 1 900 000 g / mol. The average molecular weight is expressed in g / mol for the number and average molecular weight Mn and Mw respectively. For the measurement, the concentration is Ig / L.

[0123] The viscosity of the (meth) acrylic compositions comprising at least the components al) and a2) is measured with a Brookfield viscosimeter at 23°C, according to ISO 2555:2018 "Plastics ~~ Resins in the liquid state or as emulsions or dispersions ~~ Determination of apparent viscosity using a single cylinder type rotational viscometer method".

[0124] Storage stability is measured with following method. Pour 200 g of the liquid resin in a bottle. Temper the samples at constant temperature. Check periodically samples, at the beginning every 12hours, afterwards daily and after one week weekly. Sample is considered "conform", meaning stable, if the resin remains liquid is not gelled. By remaining liquid is meant that the viscosity does no pass 20Pa*s at 23°C.[Examples]

[0125] The compounds used for the preparation of the various (meth) acrylic compositions are the following:- as (meth) acrylic polymer (Pl) : a PMMA formed by a copolymer of methyl methacrylate and of ethyl acrylate, from company Altuglas under the name Altuglas® BS 520B is used,- as (meth) acrylic monomer Ml: a methyl methacrylate stabilized with hydroquinone monomethyl ether is used,- as inhibitor (b) 4-hydroxy-2 , 2 , 6, 6-tetramethylpiperidin-l-oxyl is used,- as organic aldehyde (c) 3 , 7-demethylocta-2 , 6-dienal is used- as transition metal (d) a copper metal salt (Nouryact® CF12 - from Nouryon) is used,- as phosphite Irgafos® 168 from BASF is used,- as thioether Irganox® PS800 from BASF is used.

[0126] Five compositions are prepared by first dissolving 20 parts by weight of respective (meth) acrylic polymer (Pl) in 80 parts by weight of respective (meth) acrylic monomer (Ml) , and then adding additional components (b) , (c) , (d) and (f) at weight parts to 100 liquid (meth) acrylic syrup (LSM1) parts of according to table 1. Sample 1 does not contain any additional components (b) , (c) , (d) or (f ) .

[0127] Table 1 - compositions of the respective liquid (meth) acrylic syrups (LMS1) samples

[0128] Each sample is separated in two parts . One part is stocked at25 °C the other at 40°C. The observation over time of the five sample syrups are given in table 2, concerning the time it stays liquid and does not jell.

[0129] Table 2 - storage properties of liquid (meth) acrylic syrup(LSM1)

[0130] As can be seen in table 2, for the sample 3 with the additives needed for the polymerization the storage time and pot-life is reduced and short. With samples 4 and 5, which comprise also the additives needed for the polymerization the storage time and potlife can be increased.

Claims

CLAIMS1. A (meth) acrylic composition (MCI) comprising:(a) 100 parts by weight of a liquid (meth) acrylic syrup (LSM1) comprising :(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more (meth) acrylic monomers (Ml) , each monomer (Ml) comprising only one (meth) acrylic function per monomer,(b) an inhibitor(c) at least one organic aldehyde(d) a transition metal(e) optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator.

2. The (meth) acrylic composition (MCI) according to claim 1, comprising(b) between 0.005 part and 1 part by weight of an inhibitor(c) between 0.5 part and 10 parts by weight of one organic aldehyde(d) between 0.01 part and 4 parts by weight a transition metal.

3. The (meth) acrylic composition (MCI) according to claim 1 or 2, characterized in that inhibitor is chosen from 4-hydroxy- 2 , 2 , 6 , 6-tetramethylpiperidin-l-oxyl ( 4-Hydroxy-TEMPO or TEMPOL) or ( 2 , 2 , 6 , 6-Tetramethylpiperidin-l-yl ) oxyl (TEMPO) .

4. The (meth) acrylic composition (MCI) according to any of claims1 to 3, characterized in that the organic aldehyde comprises between 3 and 30 carbon atoms.

5. The (meth) acrylic composition (MCI) according to any of claims 1 to 3, characterized in that the organic aldehyde has a general formula R-CH=O, in which R represents a cyclic hydrocarbon-based chain or a linear or branched hydrocarbon-based chain, Rcomprising from 2 to 29 carbon atoms, preferably from 3 to 15, optionally comprising one or more unsaturation ( s ) in the form of double bonds and being optionally substituted with one or more hydroxyl groups .

6. The (meth) acrylic composition (MCI) according to any of claims 1 to 3, characterized in that the organic aldehyde is chosen from propionaldehyde, butyraldehyde, valeraldehyde, capraldehyde , benzaldehyde, geranial, neral, citronellal and also mixtures of two or more thereof in all proportions .

7. The (meth) acrylic composition (MCI) according to any of claims 1 to 6, characterized in that the transition metal is chosen from Manganese, Cobalt, Iron or Copper and more advantageously Manganese, Iron, Copper or mixtures thereof.

8. The (meth) acrylic composition (MCI) according to any of claims 1 to 6, characterized in that the transition metal is chosen from Manganese, Iron, Copper or mixtures thereof.

9. The (meth) acrylic composition (MCI) according to any of claims 1 to 8, characterized in that the liquid (meth) acrylic syrup (LSM1) comprises:(ai) from 10% by weight to 35% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 65% by weight to 90% by weight of one or more (meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer.

10. The (meth) acrylic composition (MCI) according to any of claims 1 to 8, characterized in that the liquid (meth) acrylic syrup (LSM1) comprises:(ai) from 12% by weight to 30% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 70% by weight to 88% by weight of one or more (meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer.

11. The (meth) acrylic composition (MCI) according to any of claims1 to 10, characterized in that the (meth) acrylic composition (MCI) comprises also an antioxidant (f ) , preferably a phosphite or a thioether or a mixture of phosphite and thioether.

12. The (meth) acrylic composition (MCI) according to any of claims 1 to 10, characterized in that the (meth) acrylic composition (MCI) comprises also an antioxidant (f) chosen from a phosphite or a thioether or a mixture of phosphite and thioether.

13. The (meth) acrylic composition (MCI) according to claims 11 or 12, characterized in that the antioxidant (f) is present between 0.001 part and 4 parts by weight for 100 parts by weight of the liquid (meth) acrylic syrup (LMS1) .

14. The (meth) acrylic composition (MCI) according to any of claims 1 to 13, characterized in that the polymerization initiator is chosen from diacyl peroxides, peroxy esters, peroxydicarbonates, dialkyl peroxides, peroxyacetals, hydroperoxide or peroxyketale .

15. The (meth) acrylic composition (MCI) according to any of claims 1 to 14, characterized in that the (meth) acrylic composition (MCI) comprises from 0.01 part by weight to 10 parts by weight of polymerization initiator or from 0.01 part by weight to 5 parts by weight.

16. A process to prepare the (meth) acrylic composition (MCI) according to any of claims 1 to 15, comprising the steps:(i) providing 100 parts by weight of (a) a liquid (meth) acrylic syrup (LSM1) comprising:(ai) from 1% by weight to 50% by weight of one or more (meth) acrylic polymers (Pl) , and(a2) from 50% by weight to 99% by weight of one or more(meth) acrylic monomers (Ml) , each monomer Ml comprising only one (meth) acrylic function per monomer,(ii) providing (b) an inhibitor (c) at least one organic aldehyde and (d) a transition metal,(iii) providing optionally from 0.01 part by weight to 10 parts by weight of a polymerization initiator(iv) mixing the components.

17. The process according to claim 16 providing an antioxidant (f) chosen from a phosphite or a thioether or a mixture of phosphite and thioether.

18. Use of the (meth) acrylic composition (MCI) according to any of claims 1 to 15 to prepare a (meth) acrylic polymeric material (MCP1) or (meth) acrylic polymeric composite material (MPCM1) .

19. A (meth) acrylic polymeric material (MCP1) prepared by polymerization of the (meth) acrylic composition (MCI) according to any of claims 1 to 15.

20. A (meth) acrylic polymeric composite material (MPCM1) prepared by polymerization of the (meth) acrylic composition (MCI) according to any of claims 1 to 15.

21. A process to prepare a (meth) acrylic polymeric material (MCP1) comprising the following steps:(i) providing a (meth) acrylic composition (MCI) according to any of claims 1 to 15,(ii) polymerizing the (meth) acrylic composition (MCI) .

22. A process to prepare a (meth) acrylic polymeric composite material (MCPM1) comprising the following steps:(i) providing a (meth) acrylic composition (MCI) according to any of claims 1 to 15,(ii)bringing the (meth) acrylic composition MCI in contact with a reinforcing material,( iii ) polymerizing the (meth) acrylic composition (MCI) .

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